U.S. Senate hopeful Tommy Thompson worked to reverse his campaign fortunes in a debate with opponent Tammy Baldwin on Friday, labeling her an extremist who wants to raise taxes.

Thompson opened the debate at WMVS-TV's Milwaukee studios by labeling the Democratic congresswoman "a taxer and a spender." He accused her of being out of the mainstream and failing to produce any changes in Washington.

"Baldwin doesn't have a record to run on, so all she can do is try to get people not to like me," Thompson said.

Baldwin responded by labeling partisan name-calling "crazy."

Republicans are counting on Thompson, one of the most popular politicians Wisconsin has ever produced, to win the seat and help the GOP regain control of the Senate. Baldwin, who is openly gay, has served seven relatively low-profile terms in Congress. Thompson served four terms as Wisconsin's governor.

A four-way GOP primary drained Thompson's campaign coffers, forcing him to concentrate on raising money and curtail appearances and ads. Baldwin has swooped into the void, making personal appearances around the state and running television spots.

Since the Aug. 14 primary, Baldwin has poured about $1.7 million on ads compared with about $750,000 from Thompson's campaign and the National Republican Senatorial Campaign. Outside groups have spent an additional $5.3 million for Baldwin this year compared with $3.2 million for Thompson, according to the Center for Responsive Politics.

One poll last week showed Thompson and Baldwin tied. Another conducted by the Marquette University Law School showed an 18-point turnaround, with Thompson going from a 9-point lead in August to 9 points down in September. The margin of error for both polls was about 4 percentage points.

Thompson has been trying to push back, releasing two ads last week and another on Friday. Two conservative groups, Karl Rove's political action committee and the U.S. Chamber of Commerce, spent $1.7 million on spots attacking Baldwin last week.

Baldwin and Thompson are scheduled to face off in two more debates ahead of the Nov. 6 election, including a debate on WISN 12 on Oct. 26 moderated by UpFront host Mike Gousha.